swh:1:snp:3c665ee4f67729f27f2e40193ab88e7298cf0fef
Tip revision: dc1ccc48159d63eca5089e507c82c7d22ef60839 authored by Linus Torvalds on 29 November 2013, 20:57:14 UTC
Linux 3.13-rc2
Linux 3.13-rc2
Tip revision: dc1ccc4
dslm.c
/*
* dslm.c
* Simple Disk Sleep Monitor
* by Bartek Kania
* Licensed under the GPL
*/
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <time.h>
#include <string.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <linux/hdreg.h>
#ifdef DEBUG
#define D(x) x
#else
#define D(x)
#endif
int endit = 0;
/* Check if the disk is in powersave-mode
* Most of the code is stolen from hdparm.
* 1 = active, 0 = standby/sleep, -1 = unknown */
static int check_powermode(int fd)
{
unsigned char args[4] = {WIN_CHECKPOWERMODE1,0,0,0};
int state;
if (ioctl(fd, HDIO_DRIVE_CMD, &args)
&& (args[0] = WIN_CHECKPOWERMODE2) /* try again with 0x98 */
&& ioctl(fd, HDIO_DRIVE_CMD, &args)) {
if (errno != EIO || args[0] != 0 || args[1] != 0) {
state = -1; /* "unknown"; */
} else
state = 0; /* "sleeping"; */
} else {
state = (args[2] == 255) ? 1 : 0;
}
D(printf(" drive state is: %d\n", state));
return state;
}
static char *state_name(int i)
{
if (i == -1) return "unknown";
if (i == 0) return "sleeping";
if (i == 1) return "active";
return "internal error";
}
static char *myctime(time_t time)
{
char *ts = ctime(&time);
ts[strlen(ts) - 1] = 0;
return ts;
}
static void measure(int fd)
{
time_t start_time;
int last_state;
time_t last_time;
int curr_state;
time_t curr_time = 0;
time_t time_diff;
time_t active_time = 0;
time_t sleep_time = 0;
time_t unknown_time = 0;
time_t total_time = 0;
int changes = 0;
float tmp;
printf("Starting measurements\n");
last_state = check_powermode(fd);
start_time = last_time = time(0);
printf(" System is in state %s\n\n", state_name(last_state));
while(!endit) {
sleep(1);
curr_state = check_powermode(fd);
if (curr_state != last_state || endit) {
changes++;
curr_time = time(0);
time_diff = curr_time - last_time;
if (last_state == 1) active_time += time_diff;
else if (last_state == 0) sleep_time += time_diff;
else unknown_time += time_diff;
last_state = curr_state;
last_time = curr_time;
printf("%s: State-change to %s\n", myctime(curr_time),
state_name(curr_state));
}
}
changes--; /* Compensate for SIGINT */
total_time = time(0) - start_time;
printf("\nTotal running time: %lus\n", curr_time - start_time);
printf(" State changed %d times\n", changes);
tmp = (float)sleep_time / (float)total_time * 100;
printf(" Time in sleep state: %lus (%.2f%%)\n", sleep_time, tmp);
tmp = (float)active_time / (float)total_time * 100;
printf(" Time in active state: %lus (%.2f%%)\n", active_time, tmp);
tmp = (float)unknown_time / (float)total_time * 100;
printf(" Time in unknown state: %lus (%.2f%%)\n", unknown_time, tmp);
}
static void ender(int s)
{
endit = 1;
}
static void usage(void)
{
puts("usage: dslm [-w <time>] <disk>");
exit(0);
}
int main(int argc, char **argv)
{
int fd;
char *disk = 0;
int settle_time = 60;
/* Parse the simple command-line */
if (argc == 2)
disk = argv[1];
else if (argc == 4) {
settle_time = atoi(argv[2]);
disk = argv[3];
} else
usage();
if (!(fd = open(disk, O_RDONLY|O_NONBLOCK))) {
printf("Can't open %s, because: %s\n", disk, strerror(errno));
exit(-1);
}
if (settle_time) {
printf("Waiting %d seconds for the system to settle down to "
"'normal'\n", settle_time);
sleep(settle_time);
} else
puts("Not waiting for system to settle down");
signal(SIGINT, ender);
measure(fd);
close(fd);
return 0;
}